Qucik help with transformation matrices

1. The problem statement, all variables and given/known data
Three transformations of the x-y plane are defined as follows.
[tex]T_1[/tex]: enlargement with centre O(the origin) and scale factor 5
[tex]T_2[/tex]: Anti-clockwise rotation about the origin O through an angle [tex]tan^{-1}(\frac{4}{3})[/tex]
[tex]T_3[/tex]: A stretch parallel to the x-axis(with the y-axis invariant) with scale factor 2.

The transformation [tex]T_4[/tex] is the result of applying [tex]T_1,T_2,T_3[/tex] in that order. Find the matrix which represents [tex]T_4[/tex]